2. CARBOHYDRATES.pdf

College: Applied Medical Silences Learning objectives Department: Nursing By the end of this lecture, you should be able to: C...

College: Applied Medical Silences Learning objectives Department: Nursing By the end of this lecture, you should be able to: Carbohydrate Classify carbohydrates Explain function of carbohydrates Enumerate source of carbohydrates Identify effect of high glycemic diets Identify recommended carbohydrate intake Introduction A carbohydrate molecule also includes A carbohydrate is an organic compound oxygen. that is the body‘s main source of energy. Comprised of carbon, hydrogen, and If you break down the word oxygen in a 1:2:1 ratio arranged into ‗carbohydrate‘, you‘ll find part of the basic sugar molecules names of its main components: carbon Primary fuel source for body cells. and hydrogen.  Classification of carbohydrate Functions of carbohydrates Supplies energy Protein sparing Simple sugar Prevents ketosis Carbohydrate Complex 1. Supplies energy All digestible carbohydrates namely The primary function of carbohydrates simple sugar and complex is to provide energy for cells. carbohydrates provide 4 cal /gm. Glucose is burned more efficiently and more completely than either protein or fat, and it does not leave an end product that the body must excrete. 2. Protein sparing An adequate carbohydrate intake is Consuming adequate carbohydrates to especially important whenever protein meet energy needs has the effect of needs are increased such as for wound sparing protein from being used for healing and during pregnancy and energy, leaving it available to do its lactation special functions. Although protein provides 4cal/gm just like carbohydrates 3. Prevents ketosis An increased production of ketone Fat normally supplies about half of the bodies and their accumulation in the body‘s energy requirement. bloodstream cause nausea, fatigue, loss Yet glucose fragments are needed to of appetite, and ketoacidosis efficiently and completely burn fat for energy. Without glucose, fat oxidation prematurely stops at the intermediate step of ketone body formation.  Note:- Ketone bodies: An intermediate, acidic compounds formed from the incomplete breakdown of fat when adequate glucose is not available. Grains Sources of carbohydrates Sources of carbohydrates include natural sugar in fruit and Fruit milk, starch in grains, Milk vegetables, legumes, and Nuts nuts, and the added sugar in foods with empty calories. vegetables Legumes Sugar  Serving of commonly consumed grains, fruits and vegetables contains only 1 to 3 Wheat gm of dietary fiber, legumes are rich in fiber. Rye Examples for grain: ( Wheat, barley, oats. Rye, corn and rice) and products made barley Corn with flours from grains as (bread, crackers, pasta and tortillas) Oats Recommended carbohydrate intake RDA is 130 g/day for both adults and Tortillas Bread children 50-100 g of CHO/day to prevent ketosis Recommended: 45-65% of total kcal from carbohydrates. Cracker Pasta 180-330 g of CHO/day (primarily from white bread, soda, baked goods) 50% of total kcal Worldwide the CHO intake is +70% Recommended fiber intake Problems with high sugar intakes Adequate Intake is 25 g/day for women Empty calories and 38 g/day for men Dental caries Average for both (14g/1000kacl) Glycemic index: Daily Value= 25g/day for 2000 kcal diet The blood glucose response to a given Average U.S. intake= 13-17 g/day food compared to a standard Glycemic load: Effects of Ingesting High The amount of Carbohydrate in food Glycemic Load Foods times the glycemic index for that food. Stimulates insulin release Related to structure, fiber content, Insulin increases blood triglyceride amount of processing, and levels macronutrient content Insulin increases low density lipoprotein (LDL) Insulin increase fat synthesis  Increased risk for cardiovascular Classification of diseases (CVD) carbohydrates Muscles may become resistant to insulin 1. Simple Carbohydrates Increases risk of developing diabetes 2. Complex Carbohydrates Become hungry quicker Simple Carbohydrates Complex Carbohydrates Are made up of sugars that are linked Are sugars that enter the bloodstream rapidly and provide quick energy. together chemically to form long chains. Starch – a food substance that is made Simple carbs provide calories but few and stored in most plants which provide vitamins and minerals. long-lasting energy Contains only one (mono-) or two (di-) sugars (saccharides). Examples:- fruits, honey, milk, sugars added to cookies, candies, soft drinks  Oligosaccharides Monosaccharide’s 3-10 monosaccharide‘s‘: raffinose and Disaccharides stachyose found in beans and legumes. Sucrose Not digested by the body and metabolized by bacteria in the large intestine Example: Raffinose = galactose + glucose + fructose Stachyose = galactose + galactose + glucose + fructose. Polysaccharides Starches A. Digestible polysaccharides: 3000 monosaccharides Starch Contain alpha bonds Amylose Amylopectin Amylose is straight chain Glycogen Amylopectin is branched chain B. Non-digestible polysaccharides: fibers High Glycemic Index Soluble fiber Insoluble fiber Glycogen Fibers Promotes regularity and softer, larger Storage form of glucose in animals and stool. humans Reduces hemorrhoids and diverticula. Structure is similar to amylopectin but with more complex branching Aids weight control. Numerous alpha bonds Causes a filling of fullness Found in liver (400 kcal) and muscles Slows glucose absorption (1400 kcal) Decrease in colon cancer Reduces cholesterol absorption Reduces heart disease Question???